Ford Focus ST Forum banner

1 - 16 of 16 Posts

·
Registered
Joined
·
8 Posts
Discussion Starter #1
Plan on buying a Roush Intake for my FoST. I live in CA so I need one that is CARB approved.

Please watch this video from youtube (not mine) and forward it to 0:20


It flutters. I want to know if that is safe or normal when you install n CAI on FoST.

Need a little help with why it flutters like that. :(

thank you guys!
 

·
Registered
Joined
·
424 Posts
I'm pretty sure that the video is showing the Roush intake with an aftermarket blow off valve.
 

·
Registered
Joined
·
8 Posts
Discussion Starter #3
Thank you bro! But what I’m trying to get information with is if the fluttering is safe or normal with CAI for FoST? 😌
 

·
Registered
Joined
·
551 Posts
Don't know exactly why it flutters, but I know it is normal. If the stock intake was not so restrictive and sound insoluted you would hear the same
 

·
Registered
Joined
·
108 Posts
The intake flutters even when stock, you just can't hear it because of how insulated the factory system is. What you are hearing is the sound of the air going back through the turbo blades. It is completely normal and safe on these cars because you are not under boost while it is happening. I had my tuner modify my purge line quite a bit in my tune so that my Boomba BoV would stop purging with every little movement of the throttle, so I get a lot of flutter unless I am under a decent amount of boost. Also, an intake isn't really going to net you any performance gains. If it's sound that you're looking for, then just get an aftermarket filter.
 

·
Registered
Joined
·
8 Posts
Discussion Starter #7
That’s what I am thinking just go with green filter or cobb hi flo filter then just put a turbosmart BOV. How’s that sound to you guys? Or I can do Roush and turbosmart BOV. 🧐
 

·
Registered
Joined
·
67 Posts
That’s what I am thinking just go with green filter or cobb hi flo filter then just put a turbosmart BOV. How’s that sound to you guys? Or I can do Roush and turbosmart BOV. 🧐
I had a turbosmart 50/50 BPV on my last ST and it was nice, but in hindsight i should have had the solenoid toned down alittle bit in my tune at the time.
 

·
Registered
Joined
·
8 Posts
Discussion Starter #9
The 50/50 is adjustable, prolly just need to put it hardest instead of the softest. Every video I checked with hardest has a good swoosh in it with that BOV.

My route is to go with cobb hi flow and that BOV. Haha
 

·
Registered
Joined
·
67 Posts
The 50/50 is adjustable, prolly just need to put it hardest instead of the softest. Every video I checked with hardest has a good swoosh in it with that BOV.

My route is to go with cobb hi flow and that BOV. Haha
Nice, my plan is to just upgrade to the turbosmart recirc bpv instead of the 50/50, i get enough "noise" from the greenfilter. lol
 

·
Registered
Joined
·
8 Posts
Discussion Starter #11
Did you get a check engine light when you swapped out your filter? Lots of reviews says they get a check engine light after swapped out.
 

·
Registered
Joined
·
108 Posts
I have never gotten a CEL with any of my filters and I've have both Cobb and Green filters. While it is true that you can hear the factory BPV vent with just the filter, it isn't nearly as loud as a BoV. Most seem to prefer the Turbosmart BoV because it isn't overbearing, but I wanted Boomba's BoV because it is 100% atmospherical all of the time and is the loudest.
 

·
Registered
Joined
·
1,917 Posts
I'm full bolt on I run a green filter with an RS lid And Depo intake. You can hear a little bit of flutter if you don't give it enough boost to blow off. However I'm running a turbosmart 50/50 hooked to the symposer delete on its lowest setting where the cap just covers the 2nd o-ring and I can drive without it blowing off at all if I want to. However when I get into it and it blows off perfectly fine. As for the blow off valve if your in Cali they're going to hear that go off and pull you over to investigate.
 

·
Registered
Joined
·
67 Posts
Did you get a check engine light when you swapped out your filter? Lots of reviews says they get a check engine light after swapped out.
Nope, never got a check engine light and ive had the filter in both my 14' ST for about 6 months and about a year in my current 18'.

I'm full bolt on I run a green filter with an RS lid And Depo intake. You can hear a little bit of flutter if you don't give it enough boost to blow off. However I'm running a turbosmart 50/50 hooked to the symposer delete on its lowest setting where the cap just covers the 2nd o-ring and I can drive without it blowing off at all if I want to. However when I get into it and it blows off perfectly fine. As for the blow off valve if your in Cali they're going to hear that go off and pull you over to investigate.
I thought about doing that also, my current symposer delete doesn't have a vacuum port but they are cheap enough to swap out for one, what did you do about the bpv solenoid? just left it unplugged?
 

·
Registered
Joined
·
1,917 Posts
Nope, never got a check engine light and ive had the filter in both my 14' ST for about 6 months and about a year in my current 18'.



I thought about doing that also, my current symposer delete doesn't have a vacuum port but they are cheap enough to swap out for one, what did you do about the bpv solenoid? just left it unplugged?
You leave it plugged in and you just cap it off at the solenoid. Then you run a hose from the symposer delete up to the top of the motor and attached to the hose that used to go to the solenoid. Look up Nick Baldwin's thread named blow off valve to natural vacuum source. If you have access to ntp taps I'd just drill a hole and tap it. 1/8" npt.
 
1 - 16 of 16 Posts
Top